Patent GB-839218-A (GB)
Title: Improvements in and relating to dustbin tippers
IPC: B65F3/08
Filed: 1957-09-18
Abstract: 839,218. Refuse vehicles; tipping bins. ZOLLER, H. Sept. 18, 1957 [Sept. 19, 1956; Oct. 8, 1956; April 3, 1957], No. 29437/57. Class 78 (4). A fluid-actuated dustbin tipper in which the dustbin is first tipped against a front plate and then the dustbin and the front plate are pivoted together into the entrance to a dust receptacle, comprises means to automatically throttle the flow of fluid as the bin is tipped into contact with the front-plate, then to restore the full flow and finally to shut off the fluid supply at the end of the tipping motion. As shown in Fig. 1, a dustbin 32 is moved into contact with a front plate 35 by a rocker arm 30 controlled by a piston 25 moving in a cylinder 24, and the dustbin and front plate are together tipped about the axis 29 by continued movement of the piston. Pressure fluid, in this case compressed air, is supplied through lines 1, 8 and 12 to a regulating valve 13, then passes slowly through a longitudinal bore in .the valve piston-rod 17 and emerges from a transverse bore 18, thence passing through lines 19 and 23 to the upper end of the cylinder 24. As the bin makes contact with the front plate, the piston 25 passes a port 47 and fluid passes through a line 36 to move the piston 16 of the regulating valve downwards and allow an increased fluid flow past the narrow part 17 of the rod to accelerate the tipping. When the piston 25 passes.a port 48, a piston 5 is moved upwards so that its rod 6 shuts off the fluid supply. Operation of the piston 16 may alternatively be effected by a cam on the shaft 29 (Figs. 5 and 6, not shown). For the return motion of the bin, movement of a hand valve 9 to position II causes pressure in line 19 to drop and this operates a known type of rapid venting valve 20 which vents fluid from the line 23 through a wide line 21 into the housing 27 and thence through a nozzle 51 to the atmosphere. In a modification, Fig. 4, the piston-rod 42 is fixed and the cylinder 41 acts directly on the arm 44. In this embodiment the piston 16 is cam-operated. In another embodiment, Fig. 7, in which the dustbin is raised before being tipped, the fluid passes from the line 12 through the regulating valve 13 without throttling for the initial raising motion, after which a port 58 is uncovered to raise the piston 16 and throttle the flow. Unthrottling by the port 59 and shut-off by the port 48 (shut-off valve not shown in Fig. 7) are as in the embodiment of Fig. 1. The return motion is as before, with the addition of a retarding mechanism until the dustbin reaches position IV, Fig. 7. A cone-valve 96 is moved downwards off its seat when the port 48 is uncovered on the downward motion of the piston 53 (the line 100 being connected to port 48), and the pressure-fluid pushes a piston 88 downwards to close a vent 57 in the cylinder 52. On release of the pressure the valve 96 re-seats but the vent 57 remains closed, creating a negative pressure under the piston 53 for a length of time depending on the size of an escape nozzle 99 for pressure fluid trapped between the piston 88 and the cone valve 96. The hand valve 9, Fig. 1, may be replaced by two valves 71, 80, Fig. 8, this involving the use of two hands and being stated to avoid accidents. Depression of both control knobs 75, 84 is necessary to allow tipping of the bin, and release of the lower knob causes venting of the line 19 through bores in the valve stem 76 which connect the space 77 with a vent 78. If knob 84 is released before knob 75 the bin is held in the tipped position until knob 84 is again pressed to release the pressure.